Iron-Catalysed C (Sp2)-H Borylation Enabled by Carboxylate Activation
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Contemporary Organosilicon Chemistry
Contemporary organosilicon chemistry Edited by Steve Marsden Generated on 05 October 2021, 02:13 Imprint Beilstein Journal of Organic Chemistry www.bjoc.org ISSN 1860-5397 Email: [email protected] The Beilstein Journal of Organic Chemistry is published by the Beilstein-Institut zur Förderung der Chemischen Wissenschaften. This thematic issue, published in the Beilstein Beilstein-Institut zur Förderung der Journal of Organic Chemistry, is copyright the Chemischen Wissenschaften Beilstein-Institut zur Förderung der Chemischen Trakehner Straße 7–9 Wissenschaften. The copyright of the individual 60487 Frankfurt am Main articles in this document is the property of their Germany respective authors, subject to a Creative www.beilstein-institut.de Commons Attribution (CC-BY) license. Contemporary organosilicon chemistry Steve Marsden Editorial Open Access Address: Beilstein Journal of Organic Chemistry 2007, 3, No. 4. School of Chemistry, University of Leeds, Leeds LS2 9JT, UK doi:10.1186/1860-5397-3-4 Email: Received: 06 February 2007 Steve Marsden - [email protected] Accepted: 08 February 2007 Published: 08 February 2007 © 2007 Marsden; licensee Beilstein-Institut License and terms: see end of document. Abstract Editorial for the Thematic Series on Contemporary Organosilicon Chemistry. The field of organosilicon chemistry has a rich and varied the 1990s, and equivalent to the number appearing in the much history, and has long since made the progression from chemical longer established field of organoboron chemistry -
Herbert Charles Brown, a Biographical Memoir
NATIONAL ACADEMY OF SCIENCES H E R B E R T Ch ARLES BROWN 1 9 1 2 — 2 0 0 4 A Biographical Memoir by E I-I CH I N EGIS HI Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2008 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. Photograph Credit Here. HERBERT CHARLES BROWN May 22, 1912–December 19, 2004 BY EI -ICH I NEGISHI ERBERT CHARLES BROWN, R. B. Wetherill Research Profes- Hsor Emeritus of Purdue University and one of the truly pioneering giants in the field of organic-organometallic chemistry, died of a heart attack on December 19, 2004, at age 92. As it so happened, this author visited him at his home to discuss with him an urgent chemistry-related matter only about 10 hours before his death. For his age he appeared well, showing no sign of his sudden death the next morn- ing. His wife, Sarah Baylen Brown, 89, followed him on May 29, 2005. They were survived by their only child, Charles A. Brown of Hitachi Ltd. and his family. H. C. Brown shared the Nobel Prize in Chemistry in 1979 with G. Wittig of Heidelberg, Germany. Their pioneering explorations of boron chemistry and phosphorus chemistry, respectively, were recognized. Aside from several biochemists, including V. du Vigneaud in 1955, H. C. Brown was only the second American organic chemist to win a Nobel Prize behind R. B. Woodward, in 1965. His several most significant contribu- tions in the area of boron chemistry include (1) codiscovery of sodium borohyride (1972[1], pp. -
Frontiers in Iridium-Catalyzed CH Borylation
Frontiers in Iridium-Catalyzed C-H Borylation: Attaining Novel Reactivity and Selectivity By Matthew Alan Larsen A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Chemistry in the Graduate Division of the University of California, Berkeley Committee in charge: Professor John F. Hartwig, Chair Professor Robert G. Bergman Professor Alexis T. Bell Fall 2016 Abstract Frontiers in Iridium-Catalyzed C-H Borylation: Attaining Novel Reactivity and Selectivity By Matthew Alan Larsen Doctor of Philosophy in Chemistry University of California, Berkeley Professor John F. Hartwig, Chair The following dissertation discusses the development of novel methodology for the catalytic borylation of C-H bonds and includes in-depth studies on the mechanism and selectivity of these synthetic transformations. These methods include the borylation of heteroaryl C-H bonds, the selective borylation of benzylic C-H bonds, and the directed and undirected borylation of unactivated alkyl C-H bonds. Chapter 1 contains a comprehensive review of C-H borylation methodology. This review focuses on the initial development of catalytic C-H borylation and on the state-of- the-art of methodology for the undirected and directed borylation of aryl, benzylic, and alkyl C-H bonds. Additionally, this review highlights knowledge gaps and unsolved challenges. Furthermore, this review provides the author’s opinion on future directions for research on the borylation of C-H bonds. Chapter 2 describes the study of the iridium-catalyzed borylation of heteroaryl C- H bonds. Contained is an examination of the scope of the borylation of heterocycles containing more than one heteroatom and rules for predicting the site-selectivity of this reaction. -
MICROREVIEW Reactivity of Polar Organometallic Compounds In
MICROREVIEW Reactivity of Polar Organometallic Compounds in Unconventional Reaction Media: Challenges and Opportunities Joaquin García-Álvarez,*[a] Eva Hevia,*[b] and Vito Capriati*[c] This paper is gratefully dedicated to the memory of Dr. Guy Lavigne Abstract: Developing new green solvents in designing chemical chemicals in chemical transformations is, indeed, solvents used products and processes or successfully employing the already as reaction media, which account for 80–90% of mass utilization existing ones is one of the key subjects in Green Chemistry and is in a typical pharmaceutical/fine chemical operational process. especially important in Organometallic Chemistry, which is an Thus, the solvent itself is often a critical parameter especially in interdisciplinary field. Can we advantageously use unconventional drug product manufacturing and is as well responsible for most reaction media in place of current harsh organic solvents also for waste generated in the chemical industries and laboratories.[3] polar organometallic compounds? This Microreview critically Following these considerations, some of the most critical analyses the state-of-the-art on this topic and showcases recent and intriguing questions that arise are: Can we get traditional developments and breakthroughs which are becoming new research organic solvents out of organometallic reactions?[4] Can we use directions in this field. Because metals cover a vast swath of the protic, recyclable, biodegradable, and cheap unconventional periodic table, the content is organised into three Sections solvents also for highly reactive organometallic compounds? discussing the reactivity of organometallic compounds of s-, p- and Answering these questions would not only mean to break new d-block elements in unconventional solvents. -
The Synthesis and Thermochemistry of Organoboron and Phosphorus
The Synthesis and Thermochemistry of Organoboron and Phosphorus Compounds A Thesis submitted by KHAWAJA SABIR HÜ3SAIR in candidature for the degree of Doctor of Philosophy of the University of London Royal Holloway College, Englefleld Green, Surrey. March, 1970. (U.K.;. CLASS N l / V u j AGO. No. I DA ft ACa â u L j j L À ProQuest Number: 10123886 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest. ProQuest 10123886 Published by ProQuest LLC(2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 "To all those who wished me to reach this stage" AOKNOlVLEDGmmTS The author wishes to express his gratitude to Dr# Arthur Finch for his Invaluable official supervision and encouragement. He Is highly thankful to Dr. P.J. Gardner for his entire supervision, unfailing encouragement and friendly advice. He Is also thankful to all the academic, technical and clerical staff, of the Chemistry Department, Royal Holloway College, for their co-operation and assistance. He wishes to thank the Petroleum Research Fund for a maintenance grant. ABSTRACT The synthesis and standard heats of formation of some substituted arylboroxlnes are reported. -
Présentation Powerpoint
R-M R-R’ R’-X Cross-Coupling Reactions R-M Functionnalized Organometallic Reagents R-X-R’ R-X-M C-N, C-O and C-S Bond Formation R-B(R’)2 Introduction to Organoboron Chemistry R-Si(R’)3 Introduction to Organosilicon Chemistry Carbometallation Reactions R-M R-R’ R’-X Introduction to Organosilicon Chemistry Generalities R-M Synthesis of Organosilicon Compounds R-X-R’ Hydrosilylation of Unsaturated Systems R-X-M Hiyama Cross-Coupling Hosomi-Sakurai Allylations R-B(R’)2 Brook Rearrangement R-Si(R’)3 Anion-Relay Chemistry (ARC) R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M R-R’ Introduction to Organosilicon Chemistry R’-X Generalities R-M Electronegativity s-Bond strengths (kcal.mol-1) Average Bond Length (Å) Si 1,7 C-C 83 R-X-R’ C-Si 76 C-C 1,54 Si-Si 53 C-Si 1,87 R-X-M H 2,1 C-H 83 C 2,5 Si-H 76 C-O 1,43 R-B(R’)2 Si-O 1,66 Cl 3,0 C-O 86 Si-O 108 N 3,0 R-Si(R’)3 C-N 83 O 3,5 Si-N 76 C-F 116 F 4,0 Si-F 135 R-M -
Reductive Α-Borylation of Α,Β-Unsaturated Esters Using NHC
Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Reductive a-borylation of a,b-unsaturated esters using NHC–BH3 activated by I2 as a metal-free Cite this: Chem. Sci.,2019,10,1434 a † All publication charges for this article route to -boryl esters have been paid for by the Royal Society of Chemistry James E. Radcliffe, Valerio Fasano, Ralph W. Adams, Peiran You and Michael J. Ingleson * Useful a-boryl esters can be synthesized in one step from a,b-unsaturated esters using just a simple to access NHC–BH3 (NHC ¼ N-heterocyclic carbene) and catalytic I2. The scope of this reductive a-borylation methodology is excellent and includes a range of alkyl, aryl substituted and cyclic and acyclic a,b-unsaturated esters. Mechanistic studies involving reductive borylation of a cyclic a,b-unsaturated ester with NHC–BD3/I2 indicated that concerted hydroboration of the alkene moiety in the a,b-unsaturated ester proceeds instead of a stepwise process involving initial 1,4-hydroboration; this is in contrast to the recently reported reductive a-silylation. The BH2(NHC) unit can be transformed into Creative Commons Attribution 3.0 Unported Licence. electrophilic BX2(NHC) moieties (X ¼ halide) and the ester moiety can be reduced to the alcohol with the borane unit remaining intact to form b-boryl alcohols. The use of a chiral auxiliary, 8-phenylmenthyl Received 27th September 2018 ester, also enables effective stereo-control of the newly formed C–B bond. Combined two Accepted 17th November 2018 step ester reduction/borane oxidation forms diols, including excellent e.e. -
Chemoselective Oxidation of Aryl Organoboron Systems Enabled by Boronic Acid-Selective Phase Cite This: Chem
Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Chemoselective oxidation of aryl organoboron systems enabled by boronic acid-selective phase Cite this: Chem. Sci.,2017,8,1551 transfer† John J. Molloy,a Thomas A. Clohessy,ab Craig Irving,a Niall A. Anderson,b Guy C. Lloyd-Jonesc and Allan J. B. Watson*a We report the direct chemoselective Brown-type oxidation of aryl organoboron systems containing two oxidizable boron groups. Basic biphasic reaction conditions enable selective formation and phase transfer of a boronic acid trihydroxyboronate in the presence of boronic acid pinacol (BPin) esters, while avoiding speciation equilibria. Spectroscopic investigations validate a base-promoted phase-selective discrimination of organoboron species. This phenomenon is general across a broad range of organoboron compounds and can also be used to invert conventional protecting group strategies, Received 7th September 2016 enabling chemoselective oxidation of BMIDA species over normally more reactive BPin substrates. We Accepted 25th October 2016 Creative Commons Attribution 3.0 Unported Licence. also demonstrate the selective oxidation of diboronic acid systems with chemoselectivity predictable DOI: 10.1039/c6sc04014d a priori. The utility of this method is exemplified through the development of a chemoselective oxidative www.rsc.org/chemicalscience nucleophile coupling. Introduction the broadly similar reactivity prolesofboronicacidsand esters,11 and the added complication of speciation equilibria,11–13 The use of di- and multi-boron containing systems has become establishing chemoselective control within mixed organoboron a powerful approach for the rapid synthesis of highly func- systems represents a signicant challenge. However, the identi- This article is licensed under a tionalized molecules from readily accessible starting mate- cation of new chemoselective control mechanisms would be rials.1,2 Chemoselectivity in these systems is currently achieved a fundamental advance, enabling the design and development of using only two approaches. -
Download Author Version (PDF)
Dalton Transactions Accepted Manuscript This is an Accepted Manuscript, which has been through the Royal Society of Chemistry peer review process and has been accepted for publication. Accepted Manuscripts are published online shortly after acceptance, before technical editing, formatting and proof reading. Using this free service, authors can make their results available to the community, in citable form, before we publish the edited article. We will replace this Accepted Manuscript with the edited and formatted Advance Article as soon as it is available. You can find more information about Accepted Manuscripts in the Information for Authors. Please note that technical editing may introduce minor changes to the text and/or graphics, which may alter content. The journal’s standard Terms & Conditions and the Ethical guidelines still apply. In no event shall the Royal Society of Chemistry be held responsible for any errors or omissions in this Accepted Manuscript or any consequences arising from the use of any information it contains. www.rsc.org/dalton Page 1 of 9 Dalton Transactions Journal Name RSC Publishing ARTICLE Iridium-bipyridine periodic mesoporous organosilica catalyzed direct C-H borylation Cite this: DOI: 10.1039/x0xx00000x using a pinacolborane Yoshifumi Maegawa,ab and Shinji Inagaki ab* Received 00th January 2012, Accepted 00th January 2012 DOI: 10.1039/x0xx00000x Heterogeneous catalysis for direct C-H borylation of arenes and heteroarenes in the combination of iridium (Ir) complex fixed on periodic mesoporous organosilica containing bipyridine ligands within the www.rsc.org/ framework (Ir-BPy-PMO) and pinacolborane (HBpin) is reported. Ir-BPy-PMO showed higher catalytic activity toward the borylation of benzene with inexpensive HBpin compared to expensive Manuscript bis(pinacolato)diboron (B 2pin 2). -
Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Denise N
Denise N. Meyer Synthesis of Organofluorine Compounds and Allenylboronic Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Applications Acids - Allenylboronic Synthesis of Organofluorine Compounds and Acids - Applications Including Fluorine-18 Labelling Denise N. Meyer Denise N. Meyer Raised in Lauterecken, South-West Germany, Denise studied chemistry at Johannes Gutenberg University Mainz where she obtained her Bachelor's and Master's degree. In 2017, she moved to Stockholm where she pursued her doctoral studies with Prof. Kálmán J. Szabó. ISBN 978-91-7911-490-9 Department of Organic Chemistry Doctoral Thesis in Organic Chemistry at Stockholm University, Sweden 2021 Synthesis of Organofluorine Compounds and Allenylboronic Acids - Applications Including Fluorine-18 Labelling Denise N. Meyer Academic dissertation for the Degree of Doctor of Philosophy in Organic Chemistry at Stockholm University to be publicly defended on Friday 4 June 2021 at 10.00 in Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B. Abstract This work is focused on two areas: the chemistry of organofluorine and organoboron compounds. In the first chapter, a copper-catalysed synthesis of tri- and tetrasubstituted allenylboronic acids is presented. Extension of the same method leads to allenylboronic esters. The very reactive and moisture-sensitive allenylboronic acids are further applied to the reaction with aldehydes, ketones and imines to form homopropargyl alcohols and amines. In addition, an enantioselective reaction catalysed by a BINOL organocatalyst was developed to form tertiary alcohols with adjacent quaternary carbon stereocenters. The second chapter specialises in the functionalisation of 2,2-difluoro enol silyl ethers with electrophilic reagents under mild reaction conditions. -
Boronic Acids
Boronic Acids Boronic Acids www.alfa.com INCLUDING: • Boronic Esters • Oxazaborolidine Reagents • Coupling and Hydroboration Catalysts • Phosphine Ligands • Borylation Reagents www.alfa.com Where Science Meets Service Quality Boronic Acids from Alfa Aesar Alfa Aesar is known worldwide for a variety of chemical compounds used in research and development. Recognized for purity and quality, our products and brands are backed by technical and sales teams dedicated to providing you the best service possible. In this catalog, you will find details on our line of boronic acids, esters and related compounds, which are manufactured to the same exacting standards as our full offering of over 33,000 products. Also included in this catalog is a 28-page introduction to boronic acids, their properties and applications. This catalog contains only a selection of our wide range of chemicals and materials. Also included is a selection of novel coupling catalysts and ligands. Many more products, including high purity metals, analytical products, and labware are available in our main catalog or online at www.alfa.com. Table of Contents About Us _____________________________________________________________________________ II How to Order/General Information ____________________________________________________ III Introduction __________________________________________________________________________ 1 Alkenylboronic acids and esters _____________________________________________________ 29 Alkylboronic acids and esters ________________________________________________________ -
Iridium-Catalyzed Silylation of Five-Membered Heteroarenes: High Sterically Derived Selectivity from a Pyridyl-Imidazoline Ligand Caleb Karmel‡, Camille Z
Iridium-Catalyzed Silylation of Five-Membered Heteroarenes: High Sterically Derived Selectivity from a Pyridyl-Imidazoline Ligand Caleb Karmel‡, Camille Z. Rubel‡, Elena V. Kharitonova‡, and John F. Hartwig* Department of Chemistry, University of California, Berkeley, California, 94720, United States Supporting Information Placeholder ABSTRACT: The steric effects of substituents on five-mem- Figure 1 bered rings are less pronounced than those on six-membered rings because of the difference in bond angles. Thus, the regi- oselectivities of reactions that occur with selectivities dictated by steric effects, such as the borylation of C-H bonds, have been poor in many cases. We report that the silylation of five-mem- bered ring heteroarenes occurs with high sterically derived re- gioselectivity when catalyzed by the combination of [Ir(cod)(OMe)]2 and a phenanthroline ligand or a new pyridyl- imidazoline ligand that further increases the regioselectivity. The silylation reactions with these catalysts produce high yields of heteroarylsilanes from functionalization at the most sterically accessible C–H bonds of these rings under conditions that the borylation of C–H bonds with previously reported cat- alysts formed mixtures of products or products that are unsta- ble. The heteroarylsilane products undergo cross-coupling re- actions and substitution reactions with ipso selectivity to gen- erate heteroarenes that bear halogen, aryl and perfluoroalkyl substituents. In contrast, the silylations and borylations of the C–H bonds of arenes catalyzed